Three bony point relationship

The three bony point relationship around the elbow is refers to the alignment of three prominent bony landmarks when the elbow is extended and flexed at 90 degrees.


The three bony points involves- 

1. Olecranon process of ulna 

2. Medial epicondyle of humerus 

3. Lateral epicondyle of humerus 


Normal relation: 

1. Flexion of elbow: At 90 degrees of flexion, three bony points form a roughly isosceles triangle. The olecranon process form apex, and the medial and lateral epicondyles form base.


2. Extension of elbow: During extension, these points straighten into a line, with the olecranon process in the center and both epicondyles on either side.




Clinical Significance- 

1. Fracture - Fractures of the medial epicondyle, lateral epicondyle, and olecranon process can disrupt the normal triangle shape.


2. Dislocation - In the case of elbow dislocation, olecranon processes displaced from its normal position can also alter the triangle shape.


NOTE: Supracondylar fractures of the humerus do not affect the relationship between these three bony points.


NOTE: The coronoid process of ulna is not the part of this three bony point relationship.

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